Updated dataviews submodule reference
Fixed off-by-one bug in measurement ProgressBar
Renamed topo.submodels to topo.submodel for consistency
Fixed import in gcal.ty
Compatibility fixes for switch from global AttrDict to AttrTree

The global measurement AttrDict is now switched to an AttrTree.
Since AttrTree only supports uppercase labels for its children
all lower case children had to be renamed. This includes maps,
curves, cfs, rfs, and the _activity_buffer, which are now
called Maps, Curves, CFs, RFs and ActivityBuffer.
Updated dataviews submodule reference
Fix to measurement ProgressBar for empty measurements
Updated pyflakes script to ignore redefined method names in submodel
Merge branch 'master' of github.com:ioam/topographica into color_improvements
Reverted global AttrTree to AttrDict due to GUI and backend issues

The GUI and matplotlib backends seem to throw inexplicable errors
when AttrTree is imported within base/simulation.py. Thus the
global views AttrTree had to be reverted to an AttrDict. Since the
top level views should never be touched directly, this should not
cause any issues.
Fixed GUI sheet plot mouse coordinate info
Updated imagen submodule reference
Merge branch 'master' of github.com:ioam/topographica into color_improvements
Add options to enable rotating hue and change position bound for motion